1. Field of the Invention
The present invention is related to door closure devices and, more particularly, is directed towards a regulator for controlling the opening and closing movement of a duct seal door of an ice maker in a household refrigerator and which, even more particularly, slows down the closing movement thereof while allowing relatively unimpeded opening movement.
2. Description of the Prior Art
Unique door closure devices exist for particular door closure requirements. Such requirements dictate the utilization of design criteria that take into account, for example, the speed with which the door must be opened, the speed with which the door must be closed, the spring forces necessary to effectuate or control such speeds, and the like. Other design criteria take into account the environment within which the door control device is to be situated, servicing requirements, ease of installation, manufacturing expense, reliability, and the like.
A specific application of a door control device which is recognized as being one in which the device must provide rather unique operating characteristics is in the control of a duct seal door employed for opening and closing an ice passageway of an automatic ice dispenser mounted within a household refrigerator. As recognized in U.S. Pat. No. 3,548,444 to Jacobus et al, such a door must be openable by the application of a small force, and the control device should close the door to completely seal the ice passageway upon the removal of that force. One major requirement recognized by Jacobus et al is that such a device must be operable in a manner such that the door will not close before the dispensed ice pieces enter the passageway serviced by the door.
The Jacobus et al patent teaches a device which meets the foregoing design requirements by utilizing the principle of inertia. In the Jacobus et al invention, the duct seal door is linked through speed-multiplying gears to an inertia wheel. When a power spring begins to close the door upon removal of the manual force required to keep it open, the inertial wheel, which initially tends to remain at rest, begins to rotate slowly, gradually picking up speed. This motion is transmitted to the door to slow its closure rate. Although the Jacobus et al device is widely utilized and has been found to be fairly reliable, it nevertheless requires the coaction of a large number of mechanical parts which increases costs over a less complex device and is difficult to service easily.
The most pertinent prior art U.S. patents uncovered during the course of a novelty search of the present invention include the following: U.S. Pat. Nos. 3,160,911; 3,865,216; 3,460,658; 3,365,956; 3,104,861; and 3,362,510. However, none of the foregoing are believed to teach or suggest the unique structural features of the instant invention as set forth more fully hereinbelow.